Bag works for me too. I don't get what you propose. Say I ordered 10 Red 3mm LEDs ,10 330R resistors and a couple of 16 pin DIP chips. Today I'd get a Jiffy bag with a tube for the ICs and a bag for the other items and the resistors would probably be on a strip carrier/bandolier (is that the right term.) How would they now be packaged in your brave new world?

Also there are other issues to consider e.g.:
- anti-static material? Can you get it and vacuum form it? I wouldn't want my expensive chips sent in something that wasn't anti-static.
- postage. Is this going to add weight o and/or bulk and increase costs?
- creating mould is one thing, making the actual package requires a vacuum forming machine as well.

I can see other issues such as increased handling costs to unpackage parts to fit the new packaging; e.g. resistors typically come on a paper bandolier if you buy more than a few of same value so how would that work?